Subcaliber gun mount



2 sh'o is sneet 1 \l lll v mun e. B. DAVIS; JR

SUB-GALIBER GUN MOUNT.

Nov. 23, 1948.

Filed Jan. 18'. 1546 'EEUREEE DAVIE,T T

' Nov. 23, 1948. e. B. DAVIS, JR

SUB-CALIBER GUN MOUNT 2 Sheets-Sheet 2 Filed Jan. 18, 194

Patented Nov. 23, 1948 UNITED STATES 2,454,276 SUBCALIBER GUN MOUNT George B. Davis, Jr., Green Acres, Md., assignor to the United States of America as represented by the Secretary of War Application January 18, 1946, Serial No. 642,059

3 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) field of ordnance.

More particularly it pertains to novel apparatus for securing a subcaliber gun within the chamber of a larger caliber gun.

As is Well known in the ordnance art, it is customary" to employ guns of a relatively small callher, generally known as subcaliber guns, secured to large caliber weapons to be fired in training. By this means such training may be conducted more expeditiously and in a relatively inexpensive manner by reason of'the simplicity and reduced cost of firing the smaller charges. It is also known to the prior art to employ such subcaliber guns mounted within the chambers of larger caliber weapons and wedged therein by means of a split ring device. Such prior apparatus has been generally unsatisfactory due principally to the unequal wedging forces applied by the split ring as well as the reduced working space available particularly in large caliber guns having a rearwardly neckedchamber.

It is accordingly an importantobject of the present invention to provide apparatus for attaching a subcaliber gun within the chamber of a larger caliber weapon in such manner that the wedge action may be controlled to properly align the bores of the subcaliber and the larger caliber guns.

Another object of the invention resides in the provision of a wedging collar which may be adjustably secured to a subcaliber gun for securing the latter in the forward portion of a larger caliber gun-chamber.

A still further object of the invention resides in the provision of a wedging collar for securing a subcaliber gun in the chamber of a larger caliber gun wherein clearance is provided between the threads on the subcaliber gun and the collar and bearing surfaces are provided to absorb the bearing loads.

Yet another object of the invention resides in the provision of an improved wedging element and locking lug for positioning the former with respect to the rear portion of the subcaliber gun.

Other objects and advantages of the present invention together with a complete understand ing thereof will become more readily apparent to one skilled in the art from a consideration of the following detailed specification taken in conjunction with the accompanying drawings illustrating a preferred embodiment thereof wherein:

Figure 1 is a front elevation view in partial cross section illustrating my improved apparatus in operative position between a large caliber and a subcaliber gun;

Figure 2 is a transverse View in partial cross section of the complete assembly taken along the lines 22 of Figure 1;

Figure 3 is a front elevational view of the improved wedging element forming a part of my invention;

Figure 4 is a plan view of the wedging element shown in Figure 3;

Figure 5 is an end elevational view of the wedging element of Figure 3;

Figure 6 is a plan view of the improved locking lug forming a part of my invention;

Figure '7 is a front elevational view of the locking lug of Figure 6;

Figure 8 is a plan view of the adjusting bolt forming a part of the improved apparatus;

Figure 9 is a front elevational view in partial cross section similar to Figure 1 but illustrating a modified form of the invention; and

Figure 10 is a transverse view in partial cross section of the assembly taken along the line I0lil of Figure 9.

Referring now particularly to Figure 1 of the drawings, there is illustrated a conventional 75 mm. subcaliber gun I!) within the chamber 12 of a larger caliber weapon which for purposes of illustration has been selected as a 10-inch gun. The subcaliber gun It! is provided with a threaded portion l3 located forwardly of its chamber It. A generally cylindrical collar i5 is provided with an internally threaded portion l6 having threads adapted to mesh with the threads l3 on the subcaliber gun IO. A set screw I1 is provided on the collar l5 by means of which the relative position of the threads [3 and I6 may be releasably secured. The forward outer periphery of the collar I5 is tapered in a manner similar to the taper of the forward portion of the large caliber gun chamber 12 and is adapted to be firmly wedged thereagainst, the bearing surfaces being generally designated by the reference numeral IS, The collar I5 is provided interiorly thereof with an annular bearing portion l9 adjacent its forward end adapted to engage and provide a bearing surface against a portion 2 of the subcaliber gun it.- A second interior bearingsurface or ring H is provided adjacent to the rear portion of the col- 7 55 20 and, 2 I, 22 respectively.

As illustrated particularly at the left hand portion of Figure 1 the larger caliber gun is providedv With a conventional breech block 23, a fragment of which is illustrated and includes the usual 60 obturating spindle 24, gas check pad 25, and split rings 26 and 2?. It will be noted that the obturating spindle 24 has been cut away as indicated at 28 so that its usual mushroom shape is substantially altered to provide a clearance or working space for the subcaliber gun wedging elements. These elements have been designated by reference numeral 29 and as shown particularly in Figures 3, 4 and 5, are provided with a rounded nose portion 30, a rearwardly inclined upper surface 3! and a flat top portion 32 practically parallel with the bottom surface 33. A portion of a dovetail joint 34 is formed on the left hand or rearward end of the wedge 29 and as will be particularly noted in Figures 4 and 5, the sides 35 and 36 of the wedges taper upwardly to a reduced thickness.

The structure of my improved locking lugs is best illustrated in Figures 6 and 7 wherein the lug is designated generally by reference numeral 31. Each locking lug is provided with a dovetail element 38 in its forward face adapted to firmly engage with the dovetail element 34 formed on the rear end of the wedge 29. Notches 39 and 40, respectively, are formed in the sides of the locking lugs, and cutaway portions are provided forming recesses 4| and 42 in the forward face of the lugs adjacent the notches 39 and 40. The notches 3fl48 and recesses 4|, 42 provide shoulders adapted to be engaged b the shank 43 of a bolt 44 having a head 45 and an abutting shoulder 46 thereon. The engagement of the shank 43 within the notches 39, 40 enables the bolts 44 to positively move the locking lug 31 in either direction relative to the rear base of the subcaliber gun I into which the bolts 44 are threaded in the manner illustrated in Figure 1.

As illustrated in Figure 1 the flange of a cartridge case 41 is shown in position in the subcaliber gun filling the head space 48 between the front face of the obturating spindle 24 and the rear face of the subcaliber gun breech. It will be further noted in Figure 1 that the chamber i2 is tapered at its rearward portion as well as at its forward portion so that a minimum of working space is inherentl available for adjustment of the wedging elements 29. In the modification as illustrated in Figures 9 and 10, the chamber I2 is not provided with the rearward taper illustrated in Figure l and consequently a slightly different form of wedging element may be employed, the wedging elements of Figures 9 and 10 being provided with a flat upper surface 49 instead of the two surfaces 3| and 32-provided on the wedging elements of Figures 1 to 5.

In assembling the device for training operation the collar 45 is first slid over the muzzle of the subcaliber gun l0 and the threads [3, I6 secured together in a tentative or approximate position of adjustment. The subcaliber gun may then be inserted in the bore of the larger caliber gun and the collar wedged at I 8 into the forward tapering portion of the chamber l2. The wedging elements 29 are then inserted into the inclined tapered grooves 50 formed in the outer periphery of the subcaliber gun. The dovetail elements 34 and 38 on the wedges 29 and 31, respectively, are then engaged and the bolts 44 positioned with their shanks 43 in the notches 39 and 4i) and threaded loosely into the holes 5| in the rear face of the subcalibe gun. The breech 23 may then be alternately closed and opened and the head space 48 adjusted by relative rotation of the subcaliber gun l0 and the 4 collar l5 after which the screw H is employed to prevent further relative rotation therebetween. The bolts 44 may then be tightened up to securely wedge the chamber I 4 of the subcaliber gun in position.

Since the individual wedges 29 may be separately adjusted it will be clear that the axis or line of sight of the bore of the subcaliber gun l0 may be varied with respect to the axis of the bore of the larger caliber gun in order that the operation of bore sighting may be accomplished. The subcaliber gun may then be fired in the usual manner by a suitable firin mechanism (not shown) located in the breech 23 and spindle 24.

Obviously numerous other modifications, alterations, and deviations from the specific structures set forth herein for purposes of illustration will occur to one skilled in the art without departing from the spirit or scope of the invention as set forth in the appended claims.

I claim: 7

1. In an apparatus for mounting a subcaliber gun within the chamber of a larger caliber gun, the combination of a generally cylindrical collar T threadedly engaged with the subcaliber gun and justably securing said lugs to the rear face of the subcaliber gun, means forming a plurality of radially tapered, longitudinally extending grooves arranged equidistantly from each other in the outer periphery of the subcaliber gun of varying depth, a plurality of radially tapered wedges in said grooves and having outer bearing surfaces in engagement with the rear portion of the chamber of the lar er caliber gun, means adjustably securing said wedges to said lugs, respectively, whereby the subcaliber gun is releasably held in concentric aligned position within the larger caliber gun.

2. In the apparatus as set forth in claim .1 wherein the screw means includes a plurality of bolts threaded in the rear face of the subcaliber gun and having axially spaced shoulders thereon I engageable with opposite ends of each of said lugs whereby the latter may be moved selectively toward or away from the rear face of the subcaliber gun.

3. In the apparatus as set forth'in claim 1 wherein each means adjustably securing said wedges to said lugs, respectively, is a dovetail joint which slidably secures said wedges to said locking lugs.

GEORGE E. DAVIS, JR.

REFERENCES CITED The following references are'of record in the file of this patent:

UNITED STATES PATENTS Number Name .Date

754,412 Bevans Mar. 15, 1904 757,790 Tasker Apr. 19, 1904 v FOREIGN PATENTS Number Country Date 20,258 Great Britain 1899 

